Khan.scratchpad.disable(); Jessica sells magazine subscriptions and earns $$4$ for every new subscriber she signs up. Jessica also earns a $$25$ weekly bonus regardless of how many magazine subscriptions she sells. If Jessica wants to earn at least $$39$ this week, what is the minimum number of subscriptions she needs to sell?
Solution: To solve this, let's set up an expression to show how much money Jessica will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Jessica wants to make at least $$39$ this week, we can turn this into an inequality. Amount earned this week $\geq $39$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $39$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $4 + $25 \geq $39$ $ x \cdot $4 \geq $39 - $25 $ $ x \cdot $4 \geq $14 $ $x \geq \dfrac{14}{4} \approx 3.50$ Since Jessica cannot sell parts of subscriptions, we round $3.50$ up to $4$ Jessica must sell at least 4 subscriptions this week.